The Medical Scientist Training Program (MSTP) at the University of Texas Southwestern Medical Center leads to both the Ph.D. and M.D. degrees, providing integrated and rigorous training of individuals seeking careers in biomedical research. The program involves the active participation of over 80 faculty members and scientists of the Southwestern Graduate School of Biomedical Sciences, the Southwestern Medical School, and the Howard Hughes Institute. Over 100 additional faculty members are potential participants, should students desire to work with them. Students receive four years of medical school training leading to the M.D. degree, plus comprehensive interdisciplinary research training leading to the Ph.D. degree in one of eight doctoral programs: Biological Chemistry, Cell Regulation, Genetics and Development, Immunology, Integrative Biology, Molecular Biophysics, Molecular Microbiology, or Neuroscience. The program is assembled around: (a) an extensive guidance system, to counsel students throughout their training; (b) a laboratory rotation process, extending over three summers, that both broadly trains students and aids them in the process of selecting a research area and mentor; (c) weekly seminar programs dedicated to MSTP participants; (d) an annual off-campus MSTP retreat; and (e) student participation in MSTP-related activities, such as the recruitment and admissions processes. The program selects students from a national pool of applicants, and will have a total enrollment of over 90 fellows in the fall of 2001. Approximately 15% of the program's total budget for tuition and stipends is derived from the present NIGMS award. All training takes place at the UT Southwestern Medical Center in Dallas.